It has been common practice to utilize a cover when hauling materials in the rear cargo bed of a truck. Not only does the cover protect the materials from the weather, but it also prevents these materials from being accidentally dislodged from the bed.
Accidental discharge from the cargo bed is particularly prevalent when hauling lightweight materials such as papers and leaves. A number of states have determined that a significant amount of trash found along the highways is due to improper securing of waste material in open cargo beds. In response to this, some states have enacted laws which require a cover over any materials hauled in an open cargo bed.
Many of these covers share a common feature; that is, when they are attached to the vehicle they stretch tautly in a horizontal manner across the top of the cargo bed between the cargo bed sidewalls. This provides a symmetrical appearance to the cargo bed, however it limits the amount of material that can be hauled at any one time. More particularly, these covers are unsuitable for covering materials which extend above the upper edges of the cargo bed sidewalls.
For example, in U.S. Pat. No. 4,607,876 by Reed, there is set forth a cargo bed cover which is movable from a lower position across the top edges of the cargo bed sidewalls, to an erect position above the cargo bed so as to function as a tent. Another device which acts as a truck bed cover, as well as a tent, is disclosed in U.S. Pat. No. 3,367,347 by Smith.
A cargo bed cover which is foldable in an accordian-like manner to provide access to the cargo bed is disclosed in U.S. Pat. No. 4,547,014 by Wicker. Other rear cargo bed covers which are supported on a foldable frame are disclosed in U.S. Pat. No. 3,820,840 by Forsberg, as well as U.S. Pat. No. 4,265,479 by Langston.
In U.S. Pat. No. 3,614,154 by Evans, there is disclosed a flexible cover for an open topped trailer body; the cover being attached to the trailer by means of tie down cords which are secured about cleats on the vehicle.
Helms, in U.S. Pat. No. 1,856,280, discloses a cover for the dump body of a refuse vehicle; the cover including a frame which is pivotally connected to the vehicle to permit the cover to be collapsed for access to the dump body.
Furthermore, in U.S. Pat. No. 3,051,524 by Palmer there is disclosed an edge shield for a tarpaulin cover which serves to protect the tarpaulin cover when it is stretched over the corners of the cargo bed.